With the introduction of ethanol as a fuel as well as a flex fuel additive for today's automotive engine systems, cold start performance and engine cold emissions have become an issue. There is a need to create new injection systems that can add thermal energy into the fuel prior to injection.
There are three conventional ways to add energy to the fuel: resistive heating, inductive heating and PTC (positive temperature coefficient) thermistors. The disadvantage of both resistive and PTC heating is that electrical connections need to be made to the heater in the fuel stream within the injector. The disadvantage of conventional Inductive heaters is that the volume and location (e.g., remote from the cylinders) of the heated fuel is not sufficient to create the volume of vaporized fuel to obtain a sufficient start at low temperatures.
Thus, there is a need to provide an improved fuel injector that adds thermal energy to fuel prior to injection so that a sufficient volume of vaporized fuel can be supplied to the engine.